International Journal of Plant & Soil Science

The Zinc deficiency in the soil is spreading worldwide. It can lead to decrease in soil fertility, crop yield and productivity. It is an essential micronutrient required for plants and an important dietary nutrient for the wellbeing of human beings and animals. In Nagaland, its deficiency is slowly increasing and several factors such as shifting cultivation which is also known as slash and burn, forest fire, leaching and runoff and nutrient exhaustion in the soil by the crop may be attributing to its deficiency in the soil. As Zinc deficiency is rapidly increasing all over, a soil survey on zinc availability was conducted in 83 jhum fields under rainfed condition covering 7 villages of  Zunheboto district of Nagaland during 2016-17. The soil samples were collected from the field using GPS and were analysed using standard procedure. It was observed that the Zinc deficiency ranged from 0.26 to 0.55 mg kg^-1 which indicated that its deficiency is found widespread in this part of the region. Zinc being an important micronutrient for growth and yield of crops, timely nutrient management through balanced fertilization will enhance soil fertility and crop productivity.

Maize (Zea mays L.) is an important cereal crop in the world due to its adaptability towards varied agro-climatic conditions. It is considered the Queen of the cereals. It ranks third among the cereals next to wheat and rice. The leading producer of maize is USA with 10.34 t ha ^-1 followed by Argentina (5.61 t ha^-1) and China (5.35 t ha^-1). It is the third most important cereal next to rice and wheat contributing about 10% of the total food grain production. Maize is the second most important crop next to rice in the Northeast region of India grown under rainfed upland soils. It is used for direct consumption as well as feeds to the farm animals. The area under maize in Zunheboto district of Nagaland is 10,100 hectare, however its productivity is only about 1.98 Mt ha^-1 and hence its production needs to be improved. The soils are acidic in this region and often needs to be reclaimed to increase the productivity of the maize. A field level demonstrations on acid soil management using lime was conducted based on the soil type and pH in upland jhum fields of Aotsakili and Sumi Settsu villages under Zunheboto district of Nagaland covering 2 hectares. It was observed that with the application of lime, the average mean of pH was increased from 6.2 to 6.4 and the mean yield of maize was 2300 kg ha^-1 over control (1600 kg ha^-1) with B:C ratio of 2.6 over farmers practice 2.2. This technology was found to be beneficial and suitable for neutralizing soil acidity for crop production.

The purpose of this investigation was to examine the effects of native AM fungal inoculation on the growth of Gmelina arborea, Samanea saman, Falcataria moluccana, and Enterolobium cyclocarpum under nursery and post-opencast bauxite mining field conditions. Two native AM fungi, Rhizophagus clarus and Gigaspora decipiens, were inoculated into seeds of G. arborea, S. saman, F. moluccana, and E. cyclocarpum. The seeds were sown in post-bauxite mining soil and grown in the nursery for three months. Seeds without AM inoculation were used as the control treatment. The seedlings were transplanted into a post-opencast bauxite mining field and grown for 12 months. Arbuscular mycorrhizal fungal colonization and shoot and root dry weights were measured. Under nursery conditions, G. arborea inoculated with G. decipiens increased shoot and root dry weights by 1,431 and 359 %, respectively, while shoot dry weight of E. cyclorapum inoculated with R. clarus and G. decipiens increased by 510 and 220%, respectively, in comparison with control seedlings. Root dry weight of E. cyclorapum inoculated with R. clarus increased by 224%, in comparison with control seedlings. Shoot dry weight of E. cyclorapum inoculated with R. clarus increased by 90%, in comparison with seedlings inoculated by G. decipiens. Twelve months after transplanting into post-opencast field conditions, the shoot dry weight of F. moluccana inoculated with G. decipiens was higher than that of the control seedlings by 188%. Shoot dry weight of E. cyclorapum inoculated with R. clarus and G. decipiens increased by 198% and 149%, respectively, in comparison with control seedlings. Shoot dry weight of E. cyclorapum seedlings inoculated with R. clarus was higher by 20% than that of seedlings inoculated with G. decipiens. These results show that AM fungal inoculation promotes the growth of tropical tree species on post-opencast bauxite mining land.

In the present study, seed quality status of fifteen rice varieties were evaluated for physical properties, health status and proximate composition. Physical properties like moisture content, seed purity, germination and vigor index varied between 11.77-14.67%, 96.08-98.93%, 96.50 to 99.00% and 1972.74 to 2639.76, respectively. The shoot length and root length of seedlings were from 8.93 cm to 12.99 cm and 10.89 cm to 14.22 cm, respectively. Seed health was determined by blotter test method. Five seed-borne fungi were detected and the identified fungi were Bipolaris oryzae (1.00-8.50%.), Fusarium moniliforme (0.50-3.50%), Fusarium oxysporum (0.50-9.00%.), Curvularia lunata (0.00-7.50%) and Alternaria padwickii (0.00-4.00%). Proximate composition analysis assessment was done using Association of Official Analytical Chemists (AOAC) method. The dry matter, ash, crude fiber, crude protein, crude fat and carbohydrate were between 92.52- 93.77%, 2.39-6.70%, 8.65-14.27%, 6.51-9.13%, 1.23-1.97% and 62.84-71.06%, respectively.

Bulk production and widespread end use of cresol isomers in various industrial processes result in their ubiquitous presence in the environment. Cresols are highly toxic to both fauna and flora and are included in the list of priority pollutants. This study presents the effect of o-cresol on germination of 10 different vegetable crop seeds as tested by the standard Filter Paper Method. The seeds of eggplant and long-podded cowpea were found to be highly sensitive. The most sensitive eggplant seeds were subjected to further studies in soil. Germination percentage and the seedling vigor were drastically reduced in the presence of o-cresol even at a concentration as low as 50 mg kg⁻¹ soil. A number of abnormalities in the seedlings such as stunted root and shoot growth, non-emergence of primary leaves, and negative geotropic growth were observed. Standard 2, 3, 5-tetrazoliumtrichloride test showed marked reduction in the viability of eggplant seeds proportionate to the concentration of o-cresol (0 through 200 mg L⁻¹) they were exposed to, which reached zero at 175 mg o-cresol L⁻¹, indicating the inhibition of the respiratory enzymes of the seeds. Contrary to earlier reports on the effect of phenolics on the hydrolytic enzymes of germinating seeds, in the present case an enhanced activity of amylase was observed in the presence of o-cresol (50 and 150 mg kg⁻¹ soil), whereas the protease activity was partially inhibited at higher concentration. The inhibition of seed germination by o-cresol was revoked by bioaugmentation of the soil with the cresol-degrading Pseudomonas monteilii S-CSR-0014 (2.3 x 10⁸ CFU g⁻¹ wet soil) enabling normal seed germination and seedling growth. The inoculated bacterium degraded 50 and 150 mg o-cresol kg⁻¹ soil efficiently, with concomitant growth. It can be concluded that by bacterial bioaugmentation of o-cresol-contaminated soils the inhibition of germination of crop seeds could be eliminated effectively enabling healthy seedling growth.

The present study was carried out in the field and laboratory of the Department of Seed Science and Technology, CCS Haryana Agricultural University, Hisar, Haryana during 2018-2019 to know the effect of nodal position of fruits on seed quality of okra. The parameters recorded during laboratory studies were i.e. germination, seedling length, seedling dry weight, vigour indices-1 & 2 and field studies were i.e. field emergence index, seedling establishment. The results indicated that the best nodal position of fruits for quality seed production was middle nodes (6^th to 10^th) as compared to lower nodes (1^st to 5^th) and upper nodes (11^th to 15^th) and the control.